A new method developed the double layer interaction free energe for two spherical particles by us, is extended, to the case of two cylindershape colloidal particles having equal radii(b). When a parallel body of the cylinder moves around other parallel body of cylinder, each orientation of anisometrie cylinder was taken account in calculating the interaction, energy, it is the average repulsive energy. This paper reports Monte Carlo (MC) computation on the two cylindershape colloidal particles in all relative position. MC simulation agrees with our results for κb=0.5 and κb=3.